Six-year safety and efficacy outcomes with first-line ofatumumab in recently diagnosed treatment-naive patients with...

We report ofatumumab's longer-term safety and efficacy in recently diagnosed (≤3 years) treatment-naive (RDTN) people living with relapsing multiple sclerosis (plwRMS).

Safety analyses included RDTN participants receiving at least 1 ofatumumab dose in ASCLEPIOS I/II or other ALITHIOS feeder studies (APLIOS and APOLITOS). Efficacy analyses included participants randomised to ofatumumab in ASCLEPIOS I/II and treated continuously for up to 6 years. Efficacy outcomes include annualised relapse rate (ARR), MRI lesions, no evidence of disease activity-3 (NEDA-3), cognitive processing speed, and work status.

The safety analysis included 409 RDTN plwRMS. Exposure-adjusted incidence rates of serious infections and malignancies did not increase to the cut-off date (25-Sep-2025) of 6 years. Over 6 years, mean IgG levels remained stable and IgG was above the lower limit of normal (LLN: 5.65 g/L) in 98.0% of participants at all assessments; mean IgM levels decreased but IgM remained above LLN (0.4 g/L) in 64.1% of participants at all assessments. Of 314 RDTN participants receiving ofatumumab in ASCLEPIOS I/II (efficacy analysis), 233 entered ALITHIOS, and at data cut-off 181 (77.7%, 181/233) were still receiving ofatumumab. ARR decreased from 0.112 (Year 1) to 0.030 (Year 6). An almost complete suppression of MRI lesions was observed up to Year 6. NEDA-3 at Year 6 was observed in 94.4% of participants. At 6 years, up to 70.6% of participants experienced clinically meaningful improvement in cognitive processing speed. Reduced work absenteeism versus baseline was observed.

Findings support ofatumumab's highly favourable longer-term benefit-risk profile as first-line therapy for plwRMS.